Year current US$ 1971 39999.9991059303 1972 50000.0007450581 1973 50000.0007450581 1974 79999.9982118607 1975 180000.00715255702 1976 1750000 1977 1740000.0095367401 1978 740000.009536743 1979 1220000.02861023 1980 1649999.97615814 1981 1539999.96185303 1982 1370000.00476837 1983 870000.004768372 1984 1149999.97615814 1985 1940000.0572204601 1986 1960000.03814697 1987 2579999.92370605 1988 6739999.771118159 1989 7329999.92370605 1990 11090000.1525879 1991 7309999.94277954 1992 8630000.11444092 1993 11890000.3433228 1994 6559999.94277954 1995 13449999.8092651 1996 12260000.2288818 1997 16510000.2288818 1998 21350000.3814697 1999 13140000.3433228 2000 10550000.1907349 2001 21149999.6185303 2002 20639999.3896484 2003 16979999.5422363 2004 20920000.0762939 2005 26420000.0762939 2006 20000000 2007 25219999.3133545 2008 27420000.0762939 2009 28350000.3814697 2010 20940000.5340576 2011 18569999.6948242 2012 6369999.88555908 2013 2920000.07629395 2014 90000.0035762787 2015 0 2016 980000.019073486 2017 509999.99046325695 2018 180000.00715255702 2019 239999.994635582 2020 230000.004172325